MONTPELIER — A new survey by the state of Vermont finds the number of residents without health insurance has dropped by nearly a third in the past seven years, mainly due to growth in government programs.

Results made public Thursday at a meeting of the Green Mountain Care Board show more than 61,000 Vermonters were without health coverage in 2005, or 9.8 percent of the population. The number dropped to 42,760, or 6.8 percent, by 2012.

Those with private, unsubsidized health insurance dropped from more than 369,000 residents to fewer than 346,000.

Meanwhile, Medicaid recipients were up by nearly 21,000, and there were more than 10,000 more residents on Medicare.

Those with military coverage grew by nearly 6,000 and a new state-backed program called Catamount Health had more than 10,000 subscribers.

The survey was done in August by the Market Decisions firm for the Department of Financial Regulation. Surveyors interviewed 4,610 households by cellphone and landline.

It was the fifth time since 2000 the state had commissioned such a survey.

Other findings included: Young adults were more likely to be uninsured than their elders; the median age for the uninsured was 32; the median age for those with insurance was 42. Of people 65 and older, 100 percent had insurance, thanks to Medicare. Most likely to have insurance were the poorest, who get Medicaid, and those with household incomes higher than $92,200 for a family of four.

Release of the data came as the Green Mountain Care Board continued its work to prepare Vermont for the health care overhaul under the federal Affordable Care Act. Under the new law, Americans will be able to choose from various levels of care. The lower the monthly premium, the higher the co-payments and deductibles the consumer will pay. Premiums will be subsidized with federal tax credits at many income levels.

Anya Rader Wallack, chairwoman of the Green Mountain Care Board, said monthly premiums for the various levels of coverage have not been set yet.